A High Energy Fleet
25.11.2000

Like a fleet of futuristic starcruisers, NASA's highly successful series of High Energy Astrophysical Observatory (HEAO) spacecraft appear poised over planet Earth. Labeled A, B, and C in this vintage illustration, the spacebased telescopes were known as HEAO-1, HEAO-2, and HEAO-3 respectively.

Comet Ikeya Zhang Brightens
7.03.2002

In the last week, Comet Ikeya-Zhang has become bright enough to be just visible to the unaided eye. Based on its present activity, observers are optimistic that Ikeya-Zhang will become substantially brighter. This composite...

N132D and the Color of X Rays
23.05.2002

Supernova remnant N132D shows off complex structures in this sharp, color x-ray image. Still, overall this cosmic debris from a massive star's explosive death has a strikingly simple horseshoe shape. While N132D lies 180,000 light-years distant in the Large Magellanic Cloud, the expanding remnant appears here about 80 light-years across.

Afterglow
28.05.1998

This sequence of three false color X-ray pictures from the Italian/Dutch BeppoSAX satellite follows the fading glow from a gamma-ray burster. This burster triggered orbiting gamma-ray observatories on December 14, 1997 and within 6.5 hours the sensitive X-ray cameras onboard BeppoSAX had been turned to record the first image (left) of the afterglow.

Mercury in Accentuated Color
19.03.2008

The colors of Mercury are subtle but beautiful. At first glance, our Solar System's innermost planet appears simply black and white, but images that include infrared colors normally beyond human vision accentuate a world of detail. One such image, shown above, was acquired by the robotic MESSENGER spacecraft that swung by Mercury in mid-January.

A Picturesque Venus Transit
3.06.2012

The rare transit of Venus across the face of the Sun in 2004 was one of the better-photographed events in sky history. Both scientific and artistic images flooded in from the areas that could see the transit: Europe and much of Asia, Africa, and North America.

Curiosity Before Mars: Seven Minutes of Terror
31.07.2012

Next week at this time, there may be an amazing new robotic explorer on Mars. Or there may be a new pile of junk. It all likely depends on many things going correctly in the minutes after the Mars Science Laboratory mission arrives at Mars and attempts to deploy the Curiosity rover from orbit.

Northern Mercury
1.12.2012

Innermost planet Mercury would probably not be a good location for an interplanetary winter olympics. But new results based on data from the Mercury orbiting MESSENGER spacecraft indicate that it does have substantial water ice in permanently shadowed regions within craters near its north pole.

The Gegenschein Over Chile
14.01.2014

Is the night sky darkest in the direction opposite the Sun? No. In fact, a rarely discernable faint glow known as the gegenschein (German for "counter glow") can be seen 180 degrees around from the Sun in an extremely dark sky. The gegenschein is sunlight back-scattered off small interplanetary dust particles.

Earthrise: A Video Reconstruction
23.12.2018

About 12 seconds into this video, something unusual happens. The Earth begins to rise. Never seen by humans before, the rise of the Earth over the limb of the Moon occurred 50 years ago tomorrow and surprised and amazed the crew of Apollo 8.